What is the maximum allowable plank extension for scaffold planks unless secured?

The maximum allowable plank extension for scaffold planks unless secured is 12 inches (300 mm). This standard ensures safety by minimizing the risk of plank overhang that can lead to instability or sudden failure if a worker stands on the extended portion. Keeping the extension to a maximum of 12 inches helps maintain the overall integrity of the scaffold system and provides a safe working environment.

While other extensions such as 15 inches, 18 inches, and 24 inches may seem feasible, they exceed the recommended limits intended to ensure that scaffolding setups remain secure and less prone to accidents. Adhering to the 12-inch guideline is crucial for compliance with safety regulations in construction environments.